Downhole motors are used within the oil industry for "directional" drilling. In "Directional" drilling the borehole deviates at an angle to the vertical. The angle is created by placing a bent sub in the drill string, which causes the borehole to deviate as drilling progresses. Boreholes are presently being drilled which approach a horizontal deviation. The intent of such substantially horizontal deviations is to cut across an oil bearing formation, thereby increasing production. The downhole motors used in directional drilling generally produce an eccentric motion in response to the flow of drilling fluids or "mud" pumped down the drill string from surface pumps. This eccentric motion is converted to concentric motion by a drive shaft having universal joint type connections which is secured to a bearing assembly which rotates the drill bit. It has become recognized in the art that the bend in the drill string should be placed as close as possible to the drill bit. For this reason, the practise has developed of placing a bend in a housing through which the drive shaft connecting the bearing assembly and downhole motor extends. In order to avoid the necessity of disassembling the components which make up the downhole motor assembly whenever it is necessary to alter the "bend", adjustable bent housings were developed.